Method of producing books, etc.



other.

Patented May 6, 1941 UNITED STATES PATENT orrics' Ms'rnon or PRODUCING BOOKS, s'ro. Henry H. Moreton, East Orange, N. J.

No Draining.

Application April 24, 1939, Serial No. 269,816,.

'3 Claims. (01. ass-s) This invention is a method'of treating the book sellers that relatively few sales of the best sellers are made among the poorer classes. Usually the higher priced books are bought with .the desire to preserve them in the private libraries of the purchasers, or to be continually passed from one member of the family to an- Obviously, if these works were published in editions which would be cheap enough to tempt purchases by the poorer classes, the sales of the higher priced, better editions would fall off to such an extent as to destroy any profitable earnings under copyright protection. The reader who is now unable to, gratify the desire of owning his individual copy, must perforce borrow from friends or the public library, or else rent used copies from a circulating library. The danger of contagious diseases lurking in public vola cheaply priced book which may be published at prices readily available to the poorer classes, but of such a nature that its publication will not destroy the demand for the more costly editions. This object is accomplished by printing the pages in the usual manner, and treating selected portions of the paper constituting one or more printed pages, with an actinic substance having the characteristic of changing color when exposed to light, said substance being so distributed over the printed page as to produce a non-contrasting background for the printed matter, or selected portions thereof on the page.

The invention will be hereinafter fully set forth and particularly pointed out in the claims.

One method of practicing the invention is to treat the paper of one or more printed pages, or selected portions of one or more printed pages with a solution of silver nitrate, so that when the treated pages are exposed to light, the paper or other carrier of the silver solution will turn dark, and render the printed matter illegible because of lack of contrast.

It is well known that silver nitrate crystals dissolve at ordinary temperature, in approximately half their weight of water. Therefore, a simple water solution of silver nitrate may be applied directly to the printed paper in any desired manner, as by means of a brush, ora mixture of silver nitrate and gelatine may be used. In practice,.the paper is coated with the actinic solution, or may be saturated therewith, according to the intensity of color desired, the treatment, of course, being effected under a non-actinic light. The treated book after printing and binding is wrapped in a non-actinic cover which prevents chemical change of the silver nitrate until the sealed cover is removed. Thereafter, during the reading of the book, the treated pages are successively exposed to light, in which event the .silver, nitrate gives off its oxygen to the paper ,fiber, leaving a black metallic silver as a deposit.

In applying the actinic coating, the strength of the solution may be varied according to the assumes sufiicient intensity to obscure the printed matter.

If it is desired to make the process more effective a fugitive ink of any kind may be used for the printed matter, but it is preferred to use an ink of violet color because of its well known characteristic of fading quickly. Where the fugitive ink is employed it will be readily understood that the fading of the ink increases the speed with which the printed matter will be obscured by the changed color, due to the actinic effect of light upon the silver nitrate.

A modified form of the invention consists in treating the paper with a silver bromide. If this method is used, it is preferable to render the paper hygroscopic in any well known manner, or to print directly upon hygroscopic paper. It is also preferred, although not necessary, to impregnate the paper with a developing chemical for silver bromide, such as any of the well known photographic developers for silver bromide. After the treated page has been dried in a non-actinic light, it contains both chemicals, the silver bromide and the developer, and requires moisture before the developer will become activated. After the silver bromide treatment of the selected printed pages and the completion of the book, the latter is packaged in a suitable wrapping to exclude light, and if necessary, to exclude light and moisture. In practice, when the pages have been exposed to light during the reading thereof, the silver bromide is effected by artificial light be gradually developed by the activating of the developer by the atmospheric moisture attracted to the hygroscopic papers. As a result, the surface of the treated paper will gradually turn dark, eventually producing a non-contrasting background for the printed matter.

It is well understood that silver nitrate is rather slowly affected by artificial light, and that silver bromide is very slowly affected by sun light. However, for the purposes of the present invention their actinic characteristics are ample for the purposes above described.

If it is desired to insure destruction or disintegration of the paper of the printed pages, as well as the production of a non-contrasting background for the printed matter, the paper may be impregnated with certain sodas or soda acids, such as hyposulphate of soda. Such material when left in the printed pages will combine with the moisture of the air and quickly darken or disintegrate certain types of paper, such as newsprint paper, iorinstance.

The advantages of the invention will be-readily understood by those skilled in the ant to which a the same belongs. understood that by means thereof it is possible for a copyright owner to furnish a very cheap edi- For instance, it will be readily tion, which would not only be available to the poorer classes, but would also permit of the sale of books at prices which would render it unnecessary for the readers to run the risk of contact with possibly unsanitary public volumes of a circulating library. A further advantage is that by insuring the destruction of the book after the initial reading thereof, the copyright owner may azines, pamphlets and other assemblies of superposed printed pages. Therefore, Wherever the term 'book is used in the specification and claims, it is to be understood as including all types of assemblies consisting of a plurality of superposed printed pages, whether the same is characterized as a book, magazine, pamphlet or I by any other 'technicalor popular name.

Having thus explained thenature of the invention and described an operative manner of or day light. At the same time the bromide will constructing and using the same, although without attempting to set forth all of the forms in which it may be made, or all of the forms of its use, what is claimed is:

1. The method of treating printed pages to limit the period of their legibility comprising applying an actinic solution of predetermined strength to one or more of the printed areas of one or more previously printed pages of the book, said solution having the characteristic of turning dark when exposed to light and at a speed approximately determined by the strength of the solution, whereby each coat-ed area will, when exposed to light, provide a dark non-contrasting background for the printed matter within the coated area, and controlling the depth of color to be obtained at the coated areas by the quantity of solution applied thereto.

2. The method of treating printed pages to limit the period of their legibility comprising ap-- plying an actinic solution of predetermined strength to one or more of theprinted areas of one or more previously printed pages of the book, said solution having the characteristic of turning dark when exposed to light, whereby each coated area will, when exposed to light, provide a dark non-contrasting background of the printed matter Within each coated area, and also impregnating each coated area with a photographic dev'eloping'solution capable of increasing the speed of change of color of said actinic solution, and controlling the depth of color to be obtained at each coated area by the quantity of solution applied thereto.

3. The method of treating printed pages to limit the period of their legibility comprising ap plying an actinic solution of predetermined strength to one or more of the printed areas of one or more previously printed pages of the book, said solution having the characteristic of turning dark when exposed to light and at a speed approximately determined by the strength of the solution, whereby each coated area will, whenexposed to light, provide'a dark non-contrasting background for the printed matter within the coated area, controlling the depth of color to be obtained at the coated areas by the quantity of solution applied thereto, and also impregnating each coated area with a solution of hyposulphate of soda to quickly darken the paper and to cause it to disintegrate in time.

HENRY H. MORETON. 

